The present invention relates to a traffic load density measuring system, a traffic load density measuring method, a transmitter, and a receiver, for measuring a traffic load density regarding a communication network for transmitting a packet, and a recording medium for recording a computer program product for embodying the transmitter or the receiver, and relates particularly to a traffic load density measuring system, a traffic load density measuring method, a transmitter, and a receiver, for measuring a traffic load density in a real-time system, such as a VoIP, a video streaming, or the like, and a recording medium for recording a computer program product for embodying the transmitter or the receiver.
In recent years, use of an application of a real-time system, such as a VoIP (Voice Over Internet Protocol), a video streaming, or the like, which transmits and receives data of a voice, an image, or the like between devices via a communication network, has been increased. When the application of the real-time system is used, quality of playback in reproducing the data of the voice, the image, or the like received using the application is influenced according to the situation of the communication network. For that reason, when the application of the real-time system is newly introduced, if the quality of playback deteriorates during the operation or the like, it is necessary to grasp the situation of the communication network for the purpose of solving the problem.
Conventionally, when transmission characteristics have been measured in a communication network of a packet switching method, such as the Internet or the like, a loss rate and a round trip time of an examination packet for examining a traffic load using a command called Ping have been measured, and the transmission characteristics have been measured based on the measured loss rate and round trip time. In, for example, Japanese Patent Application Laid-Open No. 2003-244238 and Japanese Patent Application Laid-Open No. 2004-007339, there is disclosed a transmission quality measuring method of the so-called passive system which statistically estimates a loss rate, a transfer delay, or the like of the packet of the communication network by capturing all of the packets.
According to the transmission quality measuring method of the passive system described in Japanese Patent Application Laid-Open No. 2003-244238 and Japanese Patent Application Laid-Open No. 2004-007339, however, since all of the packets need to be captured, when a plurality of calls are simultaneously performed, for example, the amount of packets used as an analysis object is significantly increased, so that a highly efficient capturing device is required to deal with the packets. For that reason, there is disclosed in, for example, Japanese Patent Application Laid-Open No. 2003-158550 a transmission quality measuring method of an active system which transmits the examination packet in end-to-end.
In the transmission quality measuring method of the active system, to transmit the examination packet is called a probing. According to the transmission quality measuring method disclosed in Japanese Patent Application Laid-Open No. 2003-158550, it is sufficient to perform the probing for every path between end-to-end bases, so that it is possible to estimate transmission quality without separately providing a highly efficient capturing device.